Effect of Different Types of Propolis on the Quality Characteristics of Fermented Sucuk ^†

Abstract

Fermented sucuk is a fermented food product widely consumed and enjoyed by people in Türkiye. Spices and other additives are used in the production of fermented sucuk. Due to the increasing demand for natural and healthy food consumption, the need for natural additives is also growing. Propolis is naturally obtained from honeybee hives and consists of bioactive compounds with antimicrobial and antioxidant properties. Studies have been conducted on the addition of propolis to various meat and meat products, as well as other food products. However, no studies have been found on the addition of propolis to fermented sucuk. The aim was to investigate the effect of different types of propolis (red, green, brown) on the quality characteristics of fermented sucuks. Microbiological, physicochemical, textural and sensory analyses were performed on the sucuk samples produced. It was observed that propolis did not have an adverse effect on the analysis results of propolis-added sucuks. In particular, it was determined that the growth of pathogenic bacteria was inhibited in propolis-added sucuk, resulting in low TBARS values, and other analyses yielded results in line with these standards. Based on these findings, the addition of propolis has been shown to have a positive effect on the quality of fermented sucuk.

1. Introduction

Preservation methods such as fermentation are used to prevent spoilage in meat [1]. Fermentation is applied to extend the shelf life and enhance the flavour of products such as meat, milk, fish, and vegetables [2,3]. At the end of fermentation, meat and meat products acquire a distinctive texture, colour and smell. Lactic acid bacteria (Lactobacillus, Staphylococcus, Pediococcus, Micrococcus) affect the fermentation process [4]. A low pH, high salt content and low amount of moisture in fermented meats affect the shelf life of the product. The most widely known fermented meat product is sucuk [1]. The production of fermented meat products is time-consuming and economically challenging [5]. Traditional Turkish sucuk is generally recognised as a semi-dry, fermented product. However, due to time and economic constraints, industrial producers prefer heat-treated products [6]. Sucuk production typically involves filling casings with a mixture of minced meat, fat, salt, spices, and additives, followed by curing and drying processes [7].

In addition to being consumed with pleasure, fermented products may pose a risk to health due to pathogens such as Listeria monocytogenes, Escherichia coli, Salmonella spp. and Clostridium botulinum [8]. These microorganisms can remain viable under various conditions [9]. Therefore, the use of natural preservatives in products that do not undergo heat treatment, such as fermented foods, remains important. Natural substances such as propolis have a positive effect on food stability, shelf life, and safety [8]. Propolis is a substance produced by honeybees, who collect resinous materials from various plants and process them in their hives [10]. Its chemical composition varies depending on its geographical origin. Flavonoids, aromatic acids, diterpenic acids, and phenolic compounds are responsible for its biological activity. The ethanolic propolis extract has antibacterial, antifungal, antiviral, antioxidant, and antitumour properties. Propolis is non-toxic and can be used as a food preservative [8]. Therefore, this study aimed to investigate the effect of different types of propolis on the quality characteristics of fermented sucuk.

2. Materials and Methods

Material: Minced beef and spices were obtained from a special meat combination in Afyonkarahisar, Türkiye. The propolis types used (red, green and brown) were obtained from the Faculty of Veterinary Medicine at Muğla Sıtkı Koçman University. Three different 25% propolis extracts were prepared by dissolving 500 g of propolis in 1000 mL of 70% ethanol, stirring for one week, filtering, and adjusting to a 25% resin ratio. The stock solution was stored in amber bottles.

Method: For the production of sucuk, the following ingredients were used: 80% beef (carcass meat), 20% fat (Bovine omental fat), 2% salt (containing NaNO₂-100 mg/kg), 0.6% sugar, 1% garlic, 0.7% red pepper, 0.5% black pepper, 0.9% cumin, and 0.25% piment. The mixture was divided into 10 groups: K (control), A1, A2, A3 (red propolis, 0.5%, 1%, 2%), B1, B2, B3 (green propolis, 0.5%, 1%, 2%), C1, C2, C3 (brown propolis, 0.5%, 1%, 2%). All groups were filled into 35-calibre casings, rested, and then subjected to a five-stage fermentation process (Figure 1). During the fermentation process, the airflow remained between 0.2 m/s and 0.8 m/s. After fermentation, the sucuk samples were stored at +4 °C for analysis.

Microbiological Analyses: Each sucuk sample (10 g) was homogenised with 90 mL of sterile peptone saline solution. Total aerobic mesophilic bacteria (TAMB) [11], Enterobacteriaceae [12], Coliform [13], E. coli [14], Staphylococcus [15], Lactobacillus [16], Enterococcus [17], Yeast-Mould [18] analyses were performed.

Physicochemical Analyses: pH measurement was performed using an pH meter (Testo 205, Lenzkirch, Germany). The lactic acid content was determined by titration, as described by Gökalp et al. [19]. Water activity was measured at 20 °C using a aw meter (Novasina Lab-master, Lachen, Switzerland). The TBA value was determined spectrophotometrically at 532 nm after homogenising 10 g of sample with a 7.5% TCA solution [20]. Antioxidant activity was measured using the DPPH (2,2-diphenyl-1-picrylhydrazyl) method, with absorbance read at 517 nm and calculated as a percentage [21]. Colour measurement was performed using the portable spectrophotometer (Miniscan EZ4500S, HunterLab, Reston, VA, USA) device based on the L*, a*, b* parameters.

Texture Analysis: The hardness, elasticity, stickiness, cohesiveness, and chewability values of the sucuk samples were determined using the Microstable TA-XT Plus device (Stable Micro Systems, Godalming, UK) [22].

Aroma Analysis: Qualitative volatile component analysis in sucuks was performed using a gas chromatography system and a mass spectrometer detector (Agilent Technologies, Santa Clara, CA, USA).

Sensory Analysis: Fermented sucuks were evaluated by 10 panellists and judged on appearance, colour, taste, texture, and overall liking using a 1–9 hedonic scale [23].

Statistical Analysis: Sucuk production runs were triplicated, and analyses were performed in duplicate. Differences between sucuk groups were identified using the ANOVA (Analysis of Variance) test based on the analysis results. When the p-value obtained from the ANOVA result was less than 0.05, a statistically significant difference between groups was accepted.

3. Results and Discussion

The microbiological analysis findings from the study are presented in

Table 1. Microbiological Analysis of Sucuk Samples (log cfu/g).

Days	Groups	TAMB	Enterobacteriaceae	Staphylococcus	Lactobacillus	Enterococcus	Yeast/Mould
7	K	5.25 ± 0.05 abc	2.82 ± 0.69 a	2.67 ± 0.58 a	3.79 ± 0.10 a	2.50 ± 0.17 a	2.38 ± 0.07 b
	A1	5.50 ± 0.16 a	<log 2.00	2.36 ± 0.10 b	3.42 ± 0.40 a	2.73 ± 0.51 a	2.34 ± 0.08 b
	A2	5.19 ± 0.26 bc	2.86 ± 0.69 a	2.56 ± 0.07 ab	3.52 ± 0.24 a	2.58 ± 0.28 a	2.43 ± 0.07 b
	A3	5.08 ± 0.08 c	2.46 ± 0.15 bc	2.42 ± 0.10 ab	3.26 ± 0.24 a	2.36 ± 0.10 a	2.43 ± 0.11 b
	B1	5.12 ± 0.03 c	<log 2.00	2.36 ± 0.10 b	3.59 ± 0.11 a	2.42 ± 0.10 a	2.42 ± 0.10 b
	B2	5.23 ± 0.16b c	2.30 ± 0 c	2.56 ± 0.07 ab	3.63 ± 0.13 a	2.46 ± 0.28 a	2.47 ± 0.06 b
	B3	5.09 ± 0.15 c	2.63 ± 0.31 ab	2.52 ± 0.24 ab	3.32 ± 0.28 a	2.39 ± 0.09 a	2.69 ± 0.09 a
	C1	5.13 ± 0.62 bc	2.30 ± 0 c	2.58 ± 0.17 ab	3.38 ± 0.43 a	2.42 ± 0.10 a	2.46 ± 0.16 b
	C2	5.39 ± 0.18 ab	2.62 ± 0.15 ab	2.36 ± 0.10 b	3.58 ± 0.28 a	2.40 ± 0.17 a	2.69 ± 0.21 a
	C3	5.28 ± 0.45 abc	2.40 ± 0.17 bc	2.40 ± 0.17 b	3.47 ± 0.40 a	2.42 ± 0.10 a	2.36 ± 0.10 b
12	K	6.25 ± 0.26 a	2.3933 ± 0.09 b	2.3967 ± 0.09 a	4.89 ± 0.05 a	2.67 ± 0.08 ab	2.9100 ± 0.04 a
	A1	6.00 ± 0.69 ab	2.4000 ± 0.17 b	2.3600 ± 0.10 a	4.86 ± 0.06 a	2.52 ± 0.24 ab	2.8333 ± 0.11 a
	A2	5.84 ± 0.63 abc	2.5200 ± 0.07 a	2.3600 ± 0.10 a	4.87 ± 0.08 a	2.83 ± 0.63 a	2.7933 ± 0.14 a
	A3	5.38 ± 0.17 bc	<log 2.00	2.4333 ± 0.23 a	4.45 ± 0.09 b	2.49 ± 0.10 b	2.5300 ± 0.13 bc
	B1	5.63 ± 0.21 abc	<log 2.00	2.3600 ± 0.10 a	4.66 ± 0.12 ab	2.66 ± 0.07 ab	2.7033 ± 0.29 ab
	B2	5.74 ± 0.30 abc	<log 2.00	<log 2.00	4.62 ± 0.19 ab	2.53 ± 0.26 ab	2.4967 ± 0.10 bc
	B3	5.51 ± 0.26 abc	<log 2.00	<log 2.00	4.40 ± 0.23 b	2.62 ± 0.30 ab	2.4200 ± 0.10 c
	C1	6.24 ± 0.61 a	<log 2.00	2.3833 ± 0.11 a	4.60 ± 0.23 ab	2.52 ± 0.19 ab	2.8867 ± 0.06 a
	C2	5.38 ± 0.16 bc	<log 2.00	2.3667 ± 0.06 a	4.64 ± 0.24 ab	2.45 ± 0.05 b	2.9267 ± 0.03 a
	C3	5.09 ± 0.06 c	<log 2.00	2.3600 ± 0.10 a	4.67 ± 0.45 ab	2.36 ± 0.10 b	2.5367 ± 0.10 bc
30	K	7.61 ± 0.18 ab	2.59 ± 0.19 a	2.40 ± 0.17 b	6.12 ± 0.05 b	2.81 ± 0.08 a	2.83 ± 0.16 a
	A1	7.35 ± 0.19 abc	2.54 ± 0.98 a	2.79 ± 0.20 ab	6.37 ± 0.25 ab	2.52 ± 0.24 abc	2.36 ± 0.10 c
	A2	7.34 ± 0.56 abc	2.56 ± 0.21 a	2.42 ± 0.10 b	6.70 ± 0.26 a	2.46 ± 0.28 bc	2.52 ± 0.24 bc
	A3	6.79 ± 0.12 c	<log 2.00	2.80 ± 0.44 ab	6.39 ± 0.19 ab	2.68 ± 0.19 abc	2.46 ± 0.15 bc
	B1	6.82 ± 0.44 c	2.42 ± 0.10 a	2.92 ± 0.10 ab	6.45 ± 0.06 ab	2.76 ± 0.25 ab	2.46 ± 0.15 bc
	B2	6.97 ± 0.66 abc	<log 2.00	2.63 ± 0.40 ab	6.06 ± 0.53 b	2.69 ± 0.09 ab	2.52 ± 0.07 bc
	B3	6.85 ± 0.07 bc	<log 2.00	2.53 ± 0.26 ab	6.49 ± 0.03 ab	2.80 ± 0.04 a	2.38 ± 0.14 c
	C1	7.63 ± 0.22 a	<log 2.00	2.53 ± 0.21 ab	6.42 ± 0.15 ab	2.55 ± 0.13 abc	2.94 ± 0.09 a
	C2	6.88 ± 0.70 abc	<log 2.00	3.00 ± 0.30 a	6.51 ± 0.27 ab	2.67 ± 0.58 abc	2.73 ± 0.22 ab
	C3	6.82 ± 0.17 c	<log 2.00	2.69 ± 0.36 ab	6.45 ± 0.55 ab	2.36 ± 0.10 c	2.42 ± 0.10 c
60	K	6.97 ± 0.31 a	2.84 ± 0.05 a	2.42 ± 0.10 b	6.91 ± 0.09 a	2.65 ± 0.16 a	2.99 ± 0.10 ab
	A1	6.37 ± 0.21 abcd	2.66 ± 0.12 b	2.36 ± 0.10 b	6.14 ± 0.10 bc	2.36 ± 0.10 b	3.11 ± 0.08 a
	A2	6.76 ± 0.10 ab	2.56 ± 0.10 c	2.43 ± 0.23 b	6.35 ± 0.08 b	2.42 ± 0.10 b	2.79 ± 0.27 bc
	A3	6.20 ± 0.16 bcde	<log 2.00	2.97 ± 0.35 a	5.80 ± 0.41 cd	2.40 ± 0.17 b	2.49 ± 0.10 d
	B1	6.37 ± 0.21 abcd	2.36 ± 0.10 d	2.83 ± 0.30 ab	6.03 ± 0.05 c	2.52 ± 0.07 ab	2.67 ± 0.06 cd
	B2	6.26 ± 0.25 abcde	<log 2.00	2.63 ± 0.58 ab	5.48 ± 0.29 de	<log 2.00	2.45 ± 0.05 d
	B3	5.75 ± 0.45 de	<log 2.00	2.33 ± 0.35 b	5.17 ± 0.03 e	<log 2.00	2.42 ± 0.05 d
	C1	6.59 ± 0.38 abc	<log 2.00	2.93 ± 0.13 a	6.13 ± 0.08 bc	2.62 ± 0.15 a	2.93 ± 0.10 ab
	C2	6.01 ± 0.71 cde	<log 2.00	2.93 ± 0.41 a	5.91 ± 0.71 bcd	<log 2.00	2.65 ± 0.14 cd
	C3	5.57 ± 0.63 e	<log 2.00	2.98 ± 0.28 a	5.13 ± 0.10 e	<log 2.00	2.55 ± 0.20 cd

TAMB: Total Aerobic Mesophilic Bacteria, K: Control, A1: 0.5% red propolis, A2: 1% red propolis, A3: 2% red propolis, B1: 0.5% green propolis, B2: 1% green propolis, B3: 2% green propolis, C1: 0.5% brown propolis, C2: 1% brown propolis, C3: 2% brown propolis: Different letters in the same column indicate significant differences between groups (p < 0.05).

. The TAMB count in the sucuk samples ranged from log 5.08–5.50 cfu/g on day 7, log 5.09–6.25 cfu/g on day 12, log 6.79–7.63 cfu/g on day 30, and log 5.57–6.97 cfu/g on day 60. The addition of propolis prevented an increase in TAMB. In all samples with propolis added, TAMB did not exceed log 6.76. The Enterobacteriaceae value was determined to be <log 2 cfu/g in sucuks with propolis. The highest value was observed in the control sample on days 30 and 60. It was understood that propolis limited the growth of Enterobacteriaceae. The Staphylococcus count was in the range of log 2.36–2.67 cfu/g on day 7, and <log 2 cfu/g was found in the 1% and 2% propolis samples on day 12. An average of log 2.7 cfu/g was detected on days 30 and 60. The highest value in the brown propolis group did not exceed log 2.98 cfu/g. The lowest values were determined in the A1, A2, B2, and B3 groups. Enterococcus growth was detected at a level of log 2.46 cfu/g on day 7, while on day 60, it was detected at a level of <log 2 cfu/g in some groups (B2, B3, C1, C3). The lactic acid bacteria count was 3.19 log cfu/g on day 7, 4.3 log cfu/g on day 12, 6.43 log cfu/g on day 30, and 5.8 log cfu/g on day 60. High lactic acid bacteria activity was maintained in propolis sucuks. Yeast and mould counts were log 2.21 cfu/g on day 7, log 2.40 cfu/g on day 12, log 2.53 cfu/g on day 30, and log 2.67 cfu/g on day 60. The highest value was determined in the control group. Various studies [8,24,,25,26,27] have shown that propolis inhibits microbial growth in meat products. Viera et al. [24] reported that no increase in TAMB, coliform, Salmonella, and Clostridium species was observed in salami containing 2% propolis. Çoban et al. [27] found that mesophilic and yeast-mould growth remained low in carp sucuks. Teixera et al. [8] reported that the Listeria population did not increase in meat products containing propolis for 62 days.

In the pH analysis, values ranging from 5.61 to 5.93 were found in the control group. The pH values remained stable in the red, green, and brown propolis groups. Gök et al. [28] stated in their study that the pH in sucuks varied between 5.54 and 6.00. The water activity value ranged from 0.88 to 0.68 in the control group and from 0.88 to 0.36 in the propolis groups. According to the Turkish Food Codex, acidity should be 2.5%; the samples comply with these limits. The acidity value in the control group was 2.03 on day 12 and 1.07 on day 60; in the propolis samples, it was found to be in the range of 1.07–2.17 on day 60. Soncu et al. [29] found similar titration acidity levels in fermented sucuks at the end of the fermentation process. In this study, differences in acidity values were detected between the propolis groups (

Table 2. Physicochemical Analysis of Sucuk Samples.

Days	Groups	pH	aw	Acidity (%)	Antioxidant Activity (%)	TBA (µmol mda/kg)
7	K	5.93 ± 0.15 a	0.89 ± 0.02 ab	1.97 ± 0.15 f	51.25 ± 3.71 a	0.36 ± 0.03 a
	A1	5.75 ± 0.05 bc	0.90 ± 0.003 a	1.40 ± 0.10 g	51.73 ± 3.21 a	0.35 ± 0.09 ab
	A2	5.80 ± 0.03 bc	0.88 ± 0.01 abc	1.33 ± 0.05 g	44.33 ± 10.75 a	0.29 ± 0.02 abc
	A3	5.85 ± 0.02 ab	0.87 ± 0.01 abc	2.60 ± 0.10 d	51.86 ± 3.85 a	0.25 ± 0.02 c
	B1	5.77 ± 0.02 bc	0.87 ± 0.01 abc	1.90 ± 0.10 f	50.54 ± 4.64 a	0.26 ± 0.04 abc
	B2	5.78 ± 0.03 bc	0.86 ± 0.03 bc	3.50 ± 0.10 a	42.32 ± 11.28 a	0.30 ± 0.02 abc
	B3	5.71 ± 0.04 c	0.88 ± 0.01 abc	3.00 ± 0.10 bc	52.37 ± 3.89 a	0.28 ± 0.01 abc
	C1	5.79 ± 0.03 bc	0.86 ± 0.01 bc	2.90 ± 0.10 c	51.44 ± 3.05 a	0.31 ± 0.50 abc
	C2	5.81 ± 0.02 bc	0.86 ± 0.003 c	2.33 ± 0.06 e	52.78 ± 3.47 a	0.26 ± 0.11 bc
	C3	5.82 ± 0.03 b	0.87 ± 0.02 abc	3.13 ± 0.15 b	52.30 ± 4.19 a	0.27 ± 0.01 abc
12	K	5.67 ± 0.04 a	0.87 ± 0.06 a	2.03 ± 0.65 ab	52.11 ± 3.86 a	0.22 ± 0.10 ab
	A1	5.64 ± 0.04 ab	0.91 ± 0.01 a	2.06 ± 0.40 ab	50.03 ± 11.39 b	0.17 ± 0.06 abc
	A2	5.63 ± 0.03 abc	0.88 ± 0.05 a	1.60 ± 0.20 ab	50.46 ± 5.48 a	0.16 ± 0.05 abc
	A3	5.62 ± 0.04 abcd	0.90 ± 0.01 a	1.80 ± 0.40 ab	51.92 ± 3.43 a	0.12 ± 0.02 c
	B1	5.57 ± 0.02 d	0.91 ± 0.01 a	1.40 ± 0.27 b	52.69 ± 3.58 a	0.11 ± 0.004 c
	B2	5.57 ± 0.04 cd	0.88 ± 0.01 a	1.83 ± 0.83 ab	51.63 ± 4.36 a	0.11 ± 0.003 c
	B3	5.60 ± 0.03 bcd	0.92 ± 0.01 a	1.63 ± 0.47 ab	53.70 ± 3.32 a	0.14 ± 0.02 abc
	C1	5.56 ± 0.01 d	0.90 ± 0.01 a	1.63 ± 0.35 ab	52.43 ± 3.38 a	0.18 ± 0.03 abc
	C2	5.61 ± 0.04 bcd	0.90 ± 0.01 a	2.30 ± 0.27 a	52.52 ± 3.53 a	0.23 ± 0.06 abc
	C3	5.58 ± 0.01 bcd	0.87 ± 0.05 a	2.37 ± 0.21 a	53.01 ± 3.58 a	0.14 ± 0.01 a
30	K	5.53 ± 0.03 b	0.82 ± 0.04 a	1.57 ± 0.06 ab	51.59 ± 2.18 a	0.16 ± 0.001 g
	A1	5.48 ± 0.01 c	0.79 ± 0.02 a	1.43 ± 0.06 c	50.89 ± 6.59 a	0.22 ± 0.001 de
	A2	5.53 ± 0.03 b	0.81 ± 0.02 a	1.63 ± 0.06 a	52.67 ± 3.23 a	0.20 ± 0.01 d
	A3	5.54 ± 0.01 b	0.72 ± 0.03 b	1.23 ± 0.06 e	53.02 ± 3.58 a	0.19 ± 0.001 f
	B1	5.44 ± 0.01 d	0.80 ± 0.04 a	1.60 ± 0.01 a	52.51 ± 3.27 a	0.19 ± 0.01 b
	B2	5.56 ± 0.02 a	0.82 ± 0.01 a	1.47 ± 0.11 bc	51.16 ± 3.70 a	0.32 ± 0.01 b
	B3	5.53 ± 0.01 b	0.83 ± 0.003 a	1.30 ± 0.10 de	52.44 ± 3.63 a	0.26 ± 0.03 a
	C1	5.44 ± 0.01 d	0.81 ± 0.003 a	1.47 ± 0.06 bc	49.11 ± 2.86 a	0.20 ± 0.003 ef
	C2	5.44 ± 0.01 d	0.79 ± 0.03 a	1.37 ± 0.06 cd	55.57 ± 6.36 a	0.29 ± 0.02 c
	C3	5.43 ± 0.02 d	0.78 ± 0.04 a	1.43 ± 0.06 c	50.56 ± 3.75 a	0.24 ± 0.001 d
60	K	5.61 ± 0.25 a	0.68 ± 0.05 a	1.07 ± 0.06 c	50.46 ± 5.48 a	0.07 ± 0.03 g
	A1	5.54 ± 0.21 bcd	0.41 ± 0.05 def	1.97 ± 0.06 ab	52.29 ± 3.87 a	0.18 ± 0.002 de
	A2	5.55 ± 0.15 bc	0.35 ± 0.02 efg	1.43 ± 0.12 bc	54.41 ± 3.68 a	0.13 ± 0.0007 f
	A3	5.55 ± 0.01 bcd	0.33 ± 0.02 g	1.73 ± 0.38 abc	51.08 ± 5.44 a	0.20 ± 0.0004 d
	B1	5.56 ± 0.01 b	0.56 ± 0.07 b	2.17 ± 1.01 a	53.65 ± 3.59 a	0.15 ± 0.002 f
	B2	5.53 ± 0.01 cd	0.43 ± 0.02 de	1.53 ± 0.06 abc	49.05 ± 3.96 a	0.20 ± 0.0002 d
	B3	5.52 ± 0.01 d	0.37 ± 0.01 efg	1.30 ± 0.10 bc	53.11 ± 3.33 a	0.17 ± 0.001 e
	C1	5.52 ± 0.02 d	0.37 ± 0.04 efg	1.30 ± 0.10 bc	50.19 ± 3.10 a	0.23 ± 0.006 c
	C2	5.52 ± 0.01 d	0.52 ± 0.04 bc	1.80 ± 0.35 ab	51.38 ± 4.50 a	0.28 ± 0.002 a
	C3	5.52 ± 0.03 cd	0.46 ± 0.04 cd	1.97 ± 0.06 ab	48.38 ± 1.47 a	0.25 ± 0.01 b

K: Control, A1: 0.5% red propolis, A2: 1% red propolis, A3: 2% red propolis, B1: 0.5% green propolis, B2: 1% green propolis, B3: 2% green propolis, C1: 0.5% brown propolis, C2: 1% brown propolis, C3: 2% brown propolis. ^a–g: Different letters within the same column indicate significant differences between groups (p < 0.05).

). The average antioxidant activity in the control samples of the sucuk samples was determined to be 51% on days 7, 12, 30, and 60. The average antioxidant count in the red propolis-added sucuk samples was 49.31% on day 7, 42.47% on day 12, and 52.50% on days 30 and 60. The analysis results of green propolis-added sucuk showed an average antioxidant value of 48.41% on day 7, 51.40% on days 12 and 30, and 51.92% on day 60. The average antioxidant value in brown propolis sucuks was determined to be 52% on days 7 and 12, 51.72% on day 30, and 49.98% on day 60 (Table 2).

The TBA value in the sucuk samples showed a positive effect in all propolis-enriched sucuk samples (Table 2). The average TBA value in red propolis-added sucuks was 0.3 µmol mda/kg on day 7; 0.37 µmol mda/kg on day 12; 0.2 µmol mda/kg on day 30; and 0.17 µmol mda/kg on day 60. At the same time, the average TBA amount in green propolis-added samples was observed to be 0.28 µmol mda/kg on day 7, 0.12 µmol mda/kg on day 12, 0.33 µmol mda/kg on day 30, and 0.17 µmol mda/kg on day 60. In brown propolis-added sucuk samples, the TBA levels were 0.27 µmol mda/kg on day 7, 0.18 µmol mda/kg on day 12, 0.24 µmol mda/kg on day 30, and 0.25 µmol mda/kg on day 60. When examining the control sucuks without red, green, and brown propolis, the TBA result was determined to be 0.36 µmol mda/kg on day 7, 0.22 µmol mda/kg on day 12, 0.16 µmol mda/kg on day 30, and 0.07 µmol mda/kg on day 60. Ali et al. [25] determined that the TBA value on the 12th day of their experiment on Italian sucuks was approximately 0.58 µmol mda/kg. Han and Park [30] reported in their research on 8-week-old pork products that propolis can act as a good chemical preservative, as it is naturally produced and therefore poses no harm to human health.

In colour analysis values, the brightness (L*) value ranged from 41.8 to 48.87, indicating that propolis had no adverse effect on the L value (

Table 3. Colour Analysis of Sucuk Samples.

Days	Groups	L*	a*	b*
12	K	41.80 ± 0.46 c	21.16 ± 6.90 bc	18.06 ± 2.67 a
	A1	48.87 ± 0.24 a	13.05 ± 0.14 a	10.89 ± 0.16 b
	A2	44.72 ± 0.04 abc	16.58 ± 0.01 b	14.91 ± 0.04 ab
	A3	42.46 ± 0.44 bc	13.25 ± 0.24 ab	14.08 ± 0.01 ab
	B1	45.03 ± 3.77 abc	17.19 ± 3.90 ab	15.51 ± 3.74 ab
	B2	44.02 ± 2.61 bc	14.46 ± 3.39 b	13.61 ± 5.38 ab
	B3	42.60 ± 0.84 bc	16.89 ± 1.08 ab	14.73 ± 0.48 ab
	C1	45.42 ± 4.35 abc	14.56 ± 3.40 b	15.33 ± 4.07 ab
	C2	43.86 ± 3.48 bc	17.43 ± 1.34 ab	14.86 ± 1.32 ab
	C3	46.58 ± 2.39 ab	15.51 ± 3.48 ab	11.92 ± 1.34 b
30	K	38.63 ± 0.30 g	17.34 ± 0.12 a	15.86 ± 0.22 d
	A1	45.88 ± 0.11 a	17.29 ± 0.07 a	18.27 ± 0.38 a
	A2	44.67 ± 0.21 b	17.12 ± 0.14 a	17.19 ± 0.34 c
	A3	42.28 ± 0.22 c	16.06 ± 0.22 c	15.52 ± 0.32 e
	B1	40.73 ± 0.14 e	16.54 ± 0.27 b	15.93 ± 0.04 d
	B2	41.70 ± 0.27 d	16.63 ± 0.24 b	15.95 ± 0.27 d
	B3	39.21 ± 0.05 f	16.40 ± 0.01 b	15.91 ± 0.02 d
	C1	39.25 ± 0.10 f	16.06 ± 0.10 c	15.28 ± 0.07 e
	C2	44.21 ± 0.41 b	15.05 ± 0.02 d	17.25 ± 0.05 c
	C3	41.13 ± 0.62 e	16.66 ± 0.09 b	17.61 ± 0.11 b
60	K	41.80 ± 1.03 ab	17.26 ± 0.19 a	13.64 ± 0.28 f
	A1	42.25 ± 0.54 ab	17.15 ± 0.29 a	16.94 ± 0.26 abc
	A2	42.66 ± 0.43 a	16.02 ± 0.10 b	17.71 ± 1.65 ab
	A3	41.78 ± 1.16 ab	17.34 ± 0.61 a	17.92 ± 0.25 a
	B1	42.52 ± 0.09 a	16.48 ± 0.01 ab	17.84 ± 0.01 ab
	B2	37.98 ± 0.46 c	14.59 ± 0.82 c	13.51 ± 1.28 f
	B3	41.54 ± 0.38 ab	13.33 ± 0.98 d	16.55 ± 0.14 bcd
	C1	38.64 ± 0.33 c	14.81 ± 0.18 c	16.08 ± 0.08 cde
	C2	41.28 ± 0.78 b	14.83 ± 0.22 c	15.40 ± 0.51 de
	C3	37.69 ± 0.49 c	13.63 ± 0.37 d	14.87 ± 0.16 e

L*: Brightness; a*: Redness; b*: Yellowness; K: Control, A1: 0.5% red propolis, A2: 1% red propolis, A3: 2% red propolis, B1: 0.5% green propolis, B2: 1% green propolis, B3: 2% green propolis, C1: 0.5% brown propolis, C2: 1% brown propolis, C3: 2% brown propolis: Different letters in the same column indicate significant differences between groups (p < 0.05).

). Ekiz [31] stated that the brightness value of sucuk with reduced fat content, due to the addition of lemon fibre, was in the range of 48.53–50.59 and that it did not negatively affect the brightness value of the sucuk. Similarly, Gök et al. [28] reported a value in the range of 43.16 to 44.73 in their study. The redness (a*) value was found to be slightly lower than that of the control group. As in the studies of other researchers [31], the addition of propolis did not adversely affect the redness value in sucuks. In the colour analysis of sucuks, the yellowness (b*) value did not exceed 17.74 for the inner surface in propolis-added sucuks in all groups. The yellowness values were found to be similar to those in previous sucuk studies [28,31]. In terms of colour values, the use of different types of propolis in sucuks did not produce negative results.

The texture analysis results of the sucuk samples are shown in

Table 4. Texture Analysis of Sucuk Samples.

Days	Groups	Hardness (N)	Elasticity (-)	Gumminess (N)	Chewiness (N)
12	K	23,690.34 ± 4287.42 a	0.58 ± 0.02 a	11,699.47 ± 3105.22 a	6798.79 ± 1762.50 a
	A1	12,670.84 ± 3667.49 b	0.58 ± 0.10 a	6217.80 ± 1591.51 c	3645.12 ± 1261.26 b
	A2	15,780.87 ± 1563.84 b	0.53 ± 0.11 a	6968.15 ± 1092.98 bc	3702.04 ± 1183.81 b
	A3	17,530.15 ± 4445.07 b	0.71 ± 0.08 a	9186.59 ± 2378.00 b	6654.37 ± 2276.75 a
	B1	15,271.14 ± 766.84 b	0.70 ± 0.11 a	8048.20 ± 349.19 bc	5618.04 ± 718.71 ab
	B2	12,660.21 ± 1605.48 b	0.64 ± 0.08 a	5973.63 ± 996.50 c	3837.11 ± 994.61 b
	B3	14,136.01 ± 351.37 b	0.69 ± 0.13 a	6791.83 ± 294.7 bc	4699.76 ± 925.80 ab
	C1	13,567.66 ± 2326.68 b	0.57 ± 0.11 a	5629.43 ± 214.33 c	3266.71 ± 759.23 b
	C2	14,898.93 ± 3901.76 b	0.71 ± 0.19 a	6453.07 ± 685.35 bc	4662.96 ± 1678.86 ab
	C3	14,700.93 ± 1258.99 b	0.69 ± 0.10 a	6340.67 ± 992.83 c	4356.52 ± 662.10 a
30	K	29,403.93 ± 8872.48 ab	0.52 ± 0.05 a	16,366.97 ± 4631.30 ab	11,235.25 ± 6940.27 a
	A1	13,681.21 ± 6518.82 d	0.53 ± 0.19 a	6889.99 ± 2510.86 d	3827.54 ± 2183.42 b
	A2	35,097.85 ± 1757.82 a	0.59 ± 0.03 a	18,064.36 ± 642.26 a	10687.35 ± 411.74 a
	A3	24,897.49 ± 3463.67 bc	0.57 ± 0.07 a	10,714.76 ± 4325.64 cd	6178.35 ± 3064.25 ab
	B1	23,685.83 ± 1567.65 bc	0.53 ± 0.18 a	10,842.47 ± 1058.82 cd	5828.62 ± 2639.39 ab
	B2	17,591.42 ± 2530.24 cd	0.48 ± 0.16 a	7785.39 ± 843.10 cd	3804.40 ± 1629.44 b
	B3	19,128.10 ± 2984.16 cd	0.70 ± 0.23 a	9177.83 ± 822.24 cd	6495.94 ± 2636.54 ab
	C1	16,927.48 ± 3011.10 cd	0.60 ± 0.04 a	12,726.45 ± 4756.51 bc	7686.44 ± 3101.89 ab
	C2	22,354.83 ± 1282.16 bc	0.63 ± 0.03 a	10,342.10 ± 754.75 cd	6519.11 ± 397.64 ab
	C3	18,634.57 ± 3462.05 cd	0.61 ± 0.23 a	9609.95 ± 1575.96 cd	5998.73 ± 2827.89 ab
60	K	12,553.90 ± 4132.82 a	0.47 ± 0.18 a	6148.42 ± 1059.43 b	2992.83 ± 1478.59 b
	A1	18,791.67 ± 1607.77 a	0.65 ± 0.13 a	10,704.99 ± 2278.71 a	6912.58 ± 1887.35 a
	A2	12,530.11 ± 2344.11 a	0.45 ± 0.04 a	4601.18 ± 702.03 b	2077.24 ± 360.16 b
	A3	14,699.38 ± 5358.51 a	0.50 ± 0.12 a	6058.85 ± 2485.54 b	2924.17 ± 860.20 b
	B1	16,324.82 ± 4443.84 a	0.47 ± 0.04 a	7362.09 ± 2279.35 b	3488.58 ± 1259.73 b
	B2	16,038.62 ± 3787.53 a	0.62 ± 0.12 a	5790.35 ± 1552.14 b	3704.02 ± 1534.34 b
	B3	12,683.10 ± 5581.49 a	0.61 ± 0.24 a	4682.42 ± 2557.16 b	3077.19 ± 2689.99 b
	C1	12,870.36 ± 2945.30 a	0.53 ± 0.07 a	5414.74 ± 1303.27 b	2801.51 ± 377.93 b
	C2	12,442.91 ± 3013.00 a	0.59 ± 0.03 a	5093.89 ± 1430.73 b	3035.23 ± 965.00 b
	C3	15,075.69 ± 2497.44 a	0.53 ± 0.14 a	6361.69 ± 1389.02 b	3246.25 ± 185.41 b

K: Control, A1: 0.5% red propolis, A2: 1% red propolis, A3: 2% red propolis, B1: 0.5% green propolis, B2: 1% green propolis, B3: 2% green propolis, C1: 0.5% brown propolis, C2: 1% brown propolis, C3: 2% brown propolis: Different letters in the same column indicate significant differences between groups (p < 0.05).

. In the texture analysis, hardness was measured as 25,000 in groups A1–A3, 20,000 in groups B1–B3, and 19,000 in groups C1–C3. The addition of propolis did not adversely affect hardness. Elasticity ranged from 0.53 to 0.57, stickiness from 8666 to 11,333, and chewability from 3800 to 11,830.

Sensory analysis results are presented in Figure 2. In sensory analyses, the A1–A3 group received the highest score on day 12, the C1–C3 group on day 30, and the A1–A3 group again on day 60. It was observed that as the propolis concentration increased, it had a negative impact on sensory quality. There are also differences in sensory analysis results between propolis types. The appearance, taste, aroma, and overall liking of the cross-section were positively evaluated in all samples. Gutierrez-Cortes and Mahecha [32] and Ali et al. [25] stated that the propolis additives they added did not negatively affect sensory quality and that colour and taste development increased over time.

The aroma components of the sucuk samples are presented in

Table 5. Aroma Components of Sucuk Samples (%).

No	Aroma Components	Groups
		K	A1	A2	A3	B1	B2	B3	C1	C2	C3
1	Alfa.-Copaene	0.70	1.42	-	-	-	-	0.73	0.48	0.53	-
2	Alpha.-Pinene, (-)-	0.69	1.10	-	0.52	0.64	0.74	-	-	0.60	0.89
3	Alpha.-Terpinenyl Acetate	1.09	2.01	0.90	0.79	0.66	0.68	0.68	0.79	0.77	0.95
4	Alpha.-Thujene	0.30	0.42	0.24	-	0.22	-	0.20	0.25	0.19	0.21
5	Bbeta.-Myrcene	1.21	1.77	1.17	1.04	0.81	-	1.06	1.15	0.93	1.24
6	Beta.-Phellandrene	1.90	2.88	1.67	1.31	1.45	2.03	1.70	1.82	1.49	1.84
7	Gamma.-Terpinene	5.89	9.28	4.87	4.32	4.32	5.71	6.01	6.02	4.86	6.07
8	1,6-Octadien-3-ol, 3,7-dimethyl-	2.46	4.13	2.21	2.14	1.77	1.61	1.89	1.95	1.92	1.71
9	2-Butanone (CAS)	0.26	-	0.29	0.56	0.33	0.46	0.51	0.22	--	-
10	2-CAREN-10-AL	0.59	-	1.78	1.24	1.25	1.21	1.39	0.65	1.10	0.99
11	Acetaldehyde	1.50	1.42	0.59	1.14	0.24	-	0.17	0.42	3.34	0.14
12	Acetic acid	-	0.29	-	0.70	2.27	3.02	2.85	-	-	-
13	Benzaldehyde	5.45	1.60	18.09	11.10	14.09	12.80	14.73	4.90	8.89	8.71
14	Benzene, methyl(1-methylethyl)- (CAS)	4.17	6.59	3.30	2.64	2.81	3.97	3.64	4.19	3.39	4.29
15	Bicyclo [3.1.1]heptane, 6,6-dimethyl-2-methylene-, (1S)-	4.46	7.62	3.39	3.38	3.51	6.10	4.13	4.58	3.73	3.89
16	Caryophyllene	2.65	5.97	2.72	2.09	2.07	1.64	1.98	1.92	2.10	2.71
17	Copaene	-	-	0.71	0.56	0.54	0.50	0.70	-	-	0.82
18	Cycloheptasiloxane, tetradecamethyl-	0.35	0.80	0.37	0.54	-	1.81	0.42	0.11	-	0.10
19	Diallyl disulphide	10.73	15.60	8.76	6.12	6.58	8.66	7.52	7.72	6.33	8.30
20	Disulfide, methyl 2-propenyl (CAS)	0.75	0.88	0.57	0.58	0.45	0.71	0.72	0.59	0.53	0.67
21	D-Limonene	3.99	6.42	3.35	2.61	2.78	3.83	3.58	4.00	3.14	4.13
22	Estragole	2.31	4.51	2.07	1.61	1.67	1.33	1.55	1.88	1.77	2.29
23	Eucalyptol	2.11	2.96	1.83	1.56	1.62	2.62	2.11	2.25	1.80	2.19
24	Furan, 2,3-dihydro-	17.23	7.65	4.97	5.11	8.72	9.11	5.95	13.12	4.85	10.36
25	Linalyl Acetate	0.42	0.54	0.33	0.28	0.19	-	0.35	0.26	0.21	0.25
26	p-Cymen-7-ol	3.39	2.07	0.76	3.83	-	-	0.69	1.67	1.88	2.88
27	Phenol, 2-methoxy-3-(2-propenyl)-	2.45	3.89	2.13	2.13	1.81	1.37	1.61	1.52	1.57	2.09
28	Terpinen-4-ol	0.48	0.85	0.44	0.42	0.33	0.29	0.40	0.33	0.43	0.45

K: Control, A1: 0.5% red propolis, A2: 1% red propolis, A3: 2% red propolis, B1: 0.5% green propolis, B2: 1% green propolis, B3: 2% green propolis, C1: 0.5% brown propolis, C2: 1% brown propolis, C3: 2% brown propolis.

. According to the analysis, 28 different components were identified. In the aroma component analysis, different compounds were detected in varying proportions, depending on the type of propolis used in production. It has been reported that the variability in these components and their amounts may be due to the plant-derived volatile oils and the natural structure of propolis [33].

4. Conclusions

The addition of propolis (at a rate of 0.5–2%) had a positive effect on the quality characteristics of fermented sucuks. Moisture content decreased during storage, with the ideal result observed in samples containing 0.5% red and green propolis. pH balance was maintained, and TBA increase was prevented. Propolis slowed oxidative deterioration and balanced pH, aw, and acidity values. The colour (L*, a*, b*) parameters were preserved, and the natural colour stabilising effect of propolis was determined. In conclusion, propolis, as a natural additive, increased microbial stability in fermented sucuks, extended shelf life, prevented the formation of toxic compounds, and improved sensory characteristics with positive aroma compounds at different ratios. The combination of propolis’s positive effects with fermented sucuk, a meat product, is recommended as it positively impacts product quality and produces a product with functional properties.